cregit-Linux how code gets into the kernel

Release 4.7 drivers/mtd/maps/ixp4xx.c

Directory: drivers/mtd/maps
/*
 * drivers/mtd/maps/ixp4xx.c
 *
 * MTD Map file for IXP4XX based systems. Please do not make per-board
 * changes in here. If your board needs special setup, do it in your
 * platform level code in arch/arm/mach-ixp4xx/board-setup.c
 *
 * Original Author: Intel Corporation
 * Maintainer: Deepak Saxena <dsaxena@mvista.com>
 *
 * Copyright (C) 2002 Intel Corporation
 * Copyright (C) 2003-2004 MontaVista Software, Inc.
 *
 */

#include <linux/err.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/device.h>
#include <linux/platform_device.h>

#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/partitions.h>

#include <asm/io.h>
#include <asm/mach/flash.h>

#include <linux/reboot.h>

/*
 * Read/write a 16 bit word from flash address 'addr'.
 *
 * When the cpu is in little-endian mode it swizzles the address lines
 * ('address coherency') so we need to undo the swizzling to ensure commands
 * and the like end up on the correct flash address.
 *
 * To further complicate matters, due to the way the expansion bus controller
 * handles 32 bit reads, the byte stream ABCD is stored on the flash as:
 *     D15    D0
 *     +---+---+
 *     | A | B | 0
 *     +---+---+
 *     | C | D | 2
 *     +---+---+
 * This means that on LE systems each 16 bit word must be swapped. Note that
 * this requires CONFIG_MTD_CFI_BE_BYTE_SWAP to be enabled to 'unswap' the CFI
 * data and other flash commands which are always in D7-D0.
 */
#ifndef __ARMEB__
#ifndef CONFIG_MTD_CFI_BE_BYTE_SWAP
#  error CONFIG_MTD_CFI_BE_BYTE_SWAP required
#endif


static inline u16 flash_read16(void __iomem *addr) { return be16_to_cpu(__raw_readw((void __iomem *)((unsigned long)addr ^ 0x2))); }

Contributors

PersonTokensPropCommitsCommitProp
john bowlerjohn bowler34100.00%1100.00%
Total34100.00%1100.00%


static inline void flash_write16(u16 d, void __iomem *addr) { __raw_writew(cpu_to_be16(d), (void __iomem *)((unsigned long)addr ^ 0x2)); }

Contributors

PersonTokensPropCommitsCommitProp
john bowlerjohn bowler38100.00%1100.00%
Total38100.00%1100.00%

#define BYTE0(h) ((h) & 0xFF) #define BYTE1(h) (((h) >> 8) & 0xFF) #else
static inline u16 flash_read16(const void __iomem *addr) { return __raw_readw(addr); }

Contributors

PersonTokensPropCommitsCommitProp
john bowlerjohn bowler19100.00%1100.00%
Total19100.00%1100.00%


static inline void flash_write16(u16 d, void __iomem *addr) { __raw_writew(d, addr); }

Contributors

PersonTokensPropCommitsCommitProp
john bowlerjohn bowler22100.00%1100.00%
Total22100.00%1100.00%

#define BYTE0(h) (((h) >> 8) & 0xFF) #define BYTE1(h) ((h) & 0xFF) #endif
static map_word ixp4xx_read16(struct map_info *map, unsigned long ofs) { map_word val; val.x[0] = flash_read16(map->virt + ofs); return val; }

Contributors

PersonTokensPropCommitsCommitProp
deepak saxenadeepak saxena1848.65%125.00%
david woodhousedavid woodhouse1540.54%125.00%
david vrabeldavid vrabel38.11%125.00%
john bowlerjohn bowler12.70%125.00%
Total37100.00%4100.00%

/* * The IXP4xx expansion bus only allows 16-bit wide acceses * when attached to a 16-bit wide device (such as the 28F128J3A), * so we can't just memcpy_fromio(). */
static void ixp4xx_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len) { u8 *dest = (u8 *) to; void __iomem *src = map->virt + from; if (len <= 0) return; if (from & 1) { *dest++ = BYTE1(flash_read16(src-1)); src++; --len; } while (len >= 2) { u16 data = flash_read16(src); *dest++ = BYTE0(data); *dest++ = BYTE1(data); src += 2; len -= 2; } if (len > 0) *dest++ = BYTE0(flash_read16(src)); }

Contributors

PersonTokensPropCommitsCommitProp
deepak saxenadeepak saxena7151.45%125.00%
john bowlerjohn bowler5640.58%125.00%
david vrabeldavid vrabel96.52%125.00%
jon ringlejon ringle21.45%125.00%
Total138100.00%4100.00%

/* * Unaligned writes are ignored, causing the 8-bit * probe to fail and proceed to the 16-bit probe (which succeeds). */
static void ixp4xx_probe_write16(struct map_info *map, map_word d, unsigned long adr) { if (!(adr & 1)) flash_write16(d.x[0], map->virt + adr); }

Contributors

PersonTokensPropCommitsCommitProp
deepak saxenadeepak saxena3479.07%133.33%
david vrabeldavid vrabel818.60%133.33%
john bowlerjohn bowler12.33%133.33%
Total43100.00%3100.00%

/* * Fast write16 function without the probing check above */
static void ixp4xx_write16(struct map_info *map, map_word d, unsigned long adr) { flash_write16(d.x[0], map->virt + adr); }

Contributors

PersonTokensPropCommitsCommitProp
deepak saxenadeepak saxena1955.88%125.00%
david vrabeldavid vrabel823.53%125.00%
david woodhousedavid woodhouse617.65%125.00%
john bowlerjohn bowler12.94%125.00%
Total34100.00%4100.00%

struct ixp4xx_flash_info { struct mtd_info *mtd; struct map_info map; struct resource *res; }; static const char * const probes[] = { "RedBoot", "cmdlinepart", NULL };
static int ixp4xx_flash_remove(struct platform_device *dev) { struct flash_platform_data *plat = dev_get_platdata(&dev->dev); struct ixp4xx_flash_info *info = platform_get_drvdata(dev); if(!info) return 0; if (info->mtd) { mtd_device_unregister(info->mtd); map_destroy(info->mtd); } if (plat->exit) plat->exit(); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
deepak saxenadeepak saxena7089.74%125.00%
jingoo hanjingoo han45.13%125.00%
russell kingrussell king33.85%125.00%
jamie ilesjamie iles11.28%125.00%
Total78100.00%4100.00%


static int ixp4xx_flash_probe(struct platform_device *dev) { struct flash_platform_data *plat = dev_get_platdata(&dev->dev); struct ixp4xx_flash_info *info; struct mtd_part_parser_data ppdata = { .origin = dev->resource->start, }; int err = -1; if (!plat) return -ENODEV; if (plat->init) { err = plat->init(); if (err) return err; } info = devm_kzalloc(&dev->dev, sizeof(struct ixp4xx_flash_info), GFP_KERNEL); if(!info) { err = -ENOMEM; goto Error; } platform_set_drvdata(dev, info); /* * Tell the MTD layer we're not 1:1 mapped so that it does * not attempt to do a direct access on us. */ info->map.phys = NO_XIP; info->map.size = resource_size(dev->resource); /* * We only support 16-bit accesses for now. If and when * any board use 8-bit access, we'll fixup the driver to * handle that. */ info->map.bankwidth = 2; info->map.name = dev_name(&dev->dev); info->map.read = ixp4xx_read16; info->map.write = ixp4xx_probe_write16; info->map.copy_from = ixp4xx_copy_from; info->map.virt = devm_ioremap_resource(&dev->dev, dev->resource); if (IS_ERR(info->map.virt)) { err = PTR_ERR(info->map.virt); goto Error; } info->mtd = do_map_probe(plat->map_name, &info->map); if (!info->mtd) { printk(KERN_ERR "IXP4XXFlash: map_probe failed\n"); err = -ENXIO; goto Error; } info->mtd->dev.parent = &dev->dev; /* Use the fast version */ info->map.write = ixp4xx_write16; err = mtd_device_parse_register(info->mtd, probes, &ppdata, plat->parts, plat->nr_parts); if (err) { printk(KERN_ERR "Could not parse partitions\n"); goto Error; } return 0; Error: ixp4xx_flash_remove(dev); return err; }

Contributors

PersonTokensPropCommitsCommitProp
deepak saxenadeepak saxena26977.75%215.38%
jingoo hanjingoo han226.36%215.38%
marc kleine-buddemarc kleine-budde174.91%17.69%
richard cochranrichard cochran82.31%17.69%
frans klaverfrans klaver72.02%17.69%
dmitry eremin-baryshkovdmitry eremin-baryshkov61.73%17.69%
russell kingrussell king41.16%17.69%
kay sieverskay sievers41.16%17.69%
tobias klausertobias klauser41.16%17.69%
david woodhousedavid woodhouse30.87%17.69%
david vrabeldavid vrabel20.58%17.69%
Total346100.00%13100.00%

static struct platform_driver ixp4xx_flash_driver = { .probe = ixp4xx_flash_probe, .remove = ixp4xx_flash_remove, .driver = { .name = "IXP4XX-Flash", }, }; module_platform_driver(ixp4xx_flash_driver); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("MTD map driver for Intel IXP4xx systems"); MODULE_AUTHOR("Deepak Saxena"); MODULE_ALIAS("platform:IXP4XX-Flash");

Overall Contributors

PersonTokensPropCommitsCommitProp
deepak saxenadeepak saxena61963.88%312.50%
john bowlerjohn bowler18118.68%14.17%
david vrabeldavid vrabel303.10%14.17%
jingoo hanjingoo han292.99%28.33%
david woodhousedavid woodhouse242.48%14.17%
marc kleine-buddemarc kleine-budde171.75%14.17%
russell kingrussell king171.75%14.17%
kay sieverskay sievers90.93%28.33%
tim schmielautim schmielau80.83%14.17%
richard cochranrichard cochran80.83%14.17%
frans klaverfrans klaver70.72%14.17%
dmitry eremin-baryshkovdmitry eremin-baryshkov60.62%14.17%
tobias klausertobias klauser40.41%14.17%
thomas gleixnerthomas gleixner20.21%14.17%
axel linaxel lin20.21%14.17%
jon ringlejon ringle20.21%14.17%
adrian bunkadrian bunk10.10%14.17%
artem bityutskiyartem bityutskiy10.10%14.17%
linus torvaldslinus torvalds10.10%14.17%
jamie ilesjamie iles10.10%14.17%
Total969100.00%24100.00%
Directory: drivers/mtd/maps
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
{% endraw %}